1. Field of the Invention
This invention is directed to tubing couplers or clamps, and is particularly directed to couplers for joining a length of tubing or other bracing to a shoring or scaffolding frame, stanchion, beam, or similar member.
2. Brief Description of the Prior Art
It is conventional in the shoring, scaffolding, and forming arts to use a horizontal tube or brace to join two or more stanchions together for their mutual support. Normally, such braces are held in place on the stanchions by means of double hinged couplers having one side clamped around the stanchion and the other side clamped around the brace. Each side of the conventional coupler includes a hinged member that is secured by a bolt respectively around a brace and a stanchion. Because the coupler must be bolted around both the stanchion and the brace, it is therefore tedious and time-consuming for a workman to make such installations. Typically, during installation, coupler bolts must be tightened down when at least one end of the horizontal brace is in place. Thereafter, the position of the brace on the stanchions may have to be adjusted by loosening the bolt on one stanchion, adjusting the position of the coupler thereon, and retightening the bolt, and then loosening the bolt on the other stanchion, adjusting the position of that coupler, and retightening that bolt. This work may often have to be done at some distance above the ground, requiring several ascents in order to adjust a single pair of couplers. The amount of work required to install a brace is a decided inconvenience and drawback to such conventional technique, particularly when executed by a single workman. This is aggravated because conventional coupling devices do not provide any means for provisionally holding the couplers in place while the height of the horizontal brace is adjusted at its other end.
T-channels or bolt slots have been used for years as a fastening means for bolts, especially in aluminum extrusions. Such channels or slots have been used in the shoring art for at least a decade on such things as flying forms and horizontal wall forms and, more recently, on shoring frames (for example as described in this inventor's copending application Ser. No. 185,761, filed Sept. 10, 1980). However, to the best of the inventor's belief, no coupler has ever been developed to utilize such channels or slots, much less to realize the special advantages and objectives described below in connection with the uniquely simple device embodying my invention.